Immunoassays put pay to foal play

18 January 2008

French scientists have designed tests to catch cheats who use prohibited drugs to dope racehorses.

Somatotropin, a protein hormone, increases muscle strength. Recombinant equine somatotropin is banned in horseracing since it can enhance the performance of the horse, giving them an unfair advantage. Somatotropin can be used legitimately to help repair tendon or bone injuries in horses, or to improve the condition of horses that no longer race.

Ludovic Bailly-Chouriberry, who works at both the Laboratory of Horse Racing in Verrières-le-Buisson and the National Veterinary School in Nantes, and colleagues have developed a method to test for somatotropin based on detection of antibodies raised against the hormone in serum or plasma.

Other tests to screen for somatotropin abuse, the researchers said, include the detection of insulin-like growth factor (IGF-1) whose production is also triggered by somatotropin. They hope that by detecting antibodies instead of IGF-1 a longer period for screening will be possible.

"This could also provide a cheap and important tool to indirectly detect insulin or recombinant erythropoietin misuse" - Ludovic Bailly-Chouriberry, National Veterinary School, Nantes

They identified the antibodies using two techniques: a biosensor immunoassay (BIA) and an enzyme-linked immunosorbent assay (ELISA). The developed technologies meant it was possible to detect the antibodies 80 days after administering somatotropin with BIA and 200 days with ELISA.

Bailly-Chouriberry said that this could also provide a cheap and important tool to indirectly detect insulin or recombinant erythropoietin (EPO) misuse through the detection of their antibodies, supposing it can be adapted.